Video communications systems have become increasingly popular. Videoconferencing, for example, is becoming more common in both business and residential applications. Videoconferencing permits audio as well as visual live communication between two remotely located terminals communicating over a single channel. Videoconferencing has had limited success due to, for example, unavailability of a common network interface, overly complex controls, poor video quality, limited functionality, inconvenience, and high cost. Improving video quality and functionality while simultaneously decreasing costs has proven to be difficult. For this reason, there have been opposing pressures to develop certain more expensive systems having increased video quality and functionality and certain other systems that forego the convenience and quality criteria for the sake of reducing costs.
One recent approach, that attempts to address some of the above-mentioned issues, uses a digital video camera coupled to the input port of a PC ("personal computer"). The PC is programmed to provide videoconferencing over a communications channel, such as a plain old telephone ("POTS") line. This approach is useful for applications where a PC is readily available and the user is fully familiar with downloading the software and using the PC to control the videoconferencing. However, the approach is disadvantageous for environments directed to those who are not as computer literate or not as interested in using a computer for videoconferencing. The above types of implementation are, of course, a compromise. Ideally, videoconferencing systems and equipment can be provided for both business and residential applications at reasonable cost and without sacrificing video quality, functionality, or convenience.
Another approach has been to employ a set-top videoconference unit on a conventional television monitor with a communicatively-coupled camera co-located or integral with the unit. The unit is arranged to provide an interface between the communications channel (for example, the POTS line) and a conventional telephone. The telephone is used to control the unit and provide a two-way audio interface for the videoconference. Full videoconference functionality, of course, requires a compatible unit at the other end of the communications channel. A videoconference call is typically coordinated in advance, with a call being initiated by a unit at one end of the communications channel while the unit at the other end is powered and ready to link-up with the data sent from the initiating unit. If the user of the unit at the other end does regularly have the unit powered and ready to link-up, or the unit is otherwise not available, the videoconference communication fails.